Hydraulic clutch



May 20, 1941- A. c. WHITTLESEY HYDRAULIC CLUTCH Filed Jan. 8, 1940INVENTOR. 7'1. 15 5 f V FIG. 3

ATTORNEY.

Patented May 20, 1941 HYDRAULIC CLUTCH 7 Claims.

The invention relates to a hydraulic clutch employing a positive rotaryoil pump, the discharge from which is through small ports just largeenough to allow the oil to flow freely at the idling speed of theengine. As the engine is accelerated more oil is pumped which must flowthrough the same small ports, creating a back pressure which is aresistance to the action of the pump, and, which in consequence,develops a torque. When the car has attained some predetermined speed,e. g. corresponding to 15 or 20 miles an hour in high gear,centrifugally controlled valves close the discharge ports and, since nooil can then escape from the pump, no relative movement between thedriving and driven elements is possible (except a very small amount dueto oil leakage) providing a positive drive through an oil cushion at allmedium and high speeds of the car.

Objects of the invention are to simplify and improve the fluid circuitfor the clutch, to improve the seal between the rotor and stator, tosimplify the seal for the centrifugally controlled valves, to preventreversal of the direction of rotation of the clutch, and to simplify andimprove the clutch generally.

For further details of the invention reference may be made to thedrawing wherein Fig. 1 is a vertical sectional view on lines II of Fig.2, looking in the direction of the arrows.

Fig. 2 is a sectional View on lines 2-2 of Fig. 1, looking in thedirection of the arrows.

Fig. 3 is a plan view of the right hand side of the rotor of Fig. 2.

Fig. 4 is a detailed view of one of the Valve operating mechanisms.

Referring to the drawing, the rotatable casing I is adapted to contain afluid, such as oil, and comprises a ring 2 to which is secured endplates 3 and 4 by means of bolts such as 5 and 6 respectively. Securedto end plate 3 by bolts such as l is a hub 8 which is adapted to besecured, in a conventional manner, to the crank shaft of the engine ofan automobile. End plates 3 ,and 4 have aligned bearings 9 and lilrespectively in which is rotatably mounted a shaft H which is adapted tobe secured to the transmission of the automobile. Secured to shaft H bykey I2 is the rotor l3. Key l2 permits rotor I3 to slide axially onshaft II in order to permit rotor l3 to be properly aligned with thecasing ring 2.

Ring 2 has a pair of circumferentially spaced eccentric grooves orrecesses l4 and I5, as shown in Fig. 1, the corresponding inner faces l6and ll of the ring 2 forming the outer walls of the pump chambers l8 andI9 respectively.

The rotor l3 comprises a rotor ring 29 having a circular periphery 2|which forms the inner walls of the pump chambers 58 and IS. The ring 20has three arms or spokes 22, 23, and 24 each of which has a radialrecess 25, 26, and 21 respectively and in each such recess is mounted avane 28, 29, and 39 respectively, urged outwardly by springs 3!, 32, and33 respectively. Each of the vanes 28, 29, and 3E) is of the same widthas the width of the pump chambers l8 and it. To the left side of rotorring 2! as shown in Fig. 2, is a disc 35 secured thereto by bolts suchas 35. Disc 3% forms one side wall of the pump chambers l8 and i9 andhas three equally spaced inlet ports 38, 31, and 33 arranged on theleading side of their respective vanes 29, 28, and 30. Between the armsor spokes 22, 23, and 24 are provided ports 39, 4G and Al which permitthe oil or other fluid to fiow to the left as seen in Fig. 2, to thefluid chamber of which a side wall is formed by end plate 3 so that thisoil may enter the inlet ports 36, 37, and 38 lead-' a ing to the pumpchambers l8 and 19. Disc 34 has radial sealing contact and alsoperipheral contact with the casing ring 2 by reason of the fact that theperiphery of this disc 34 is fitted to the inside of ring 2, and byreason of the fact that the right hand side of disc 34 as seen in Fig. 2bears against the flat circular bearing surface 42 on the ring 2.Secured to the right hand side of rotor ring 29, as seen in Fig. 2, bymeans of bolts such as 43 is a circular disc 44 which forms the righthand side wall of the pump chambers I8 and I3. Disc 44 also hasperipheral and radial sealing contact with the casing ring 2 in the samemanner as above described for disc 34, namely the periphery of disc 44has a bearing contact with the inner surface of casing ring 2, and theleft side of disc 44 has sliding engagement with the fiat annularsurface 45 on the ring 2. The casing ring 2, the rotor ring 20 and thediscs 34 and &4 form walls of the pump chambers l8 and I 9.

Disc 45 has three ports of the same size and directly opposite the ports39, ib and ll one of these ports being illustrated on dotted lines at 41in Fig. 2, and all of them showing in Fig, 3. The ports 6! permit theoil toflow from the right hand side of the casing I through disc 34, andit then flows through the ports 39, 40 and 4| to the left hand sidethereof.

Disc 44 is provided with three equally spaced outlet ports, one of whichis shown at 48 in Fig. 2,

arranged on the opposite sides of the vanes 28, 29 and 30 from the inletports 36, 31 and 38. The position of the outlet port 48, with respect tothe vane 29 and the inlet port 36, is illustrated by the broken circle48' in Fig. 1. Similarly the broken circle 49' illustrates the relativeposition of a second outlet port similar to the outlet 48 and the brokencircle 50', illustrates the relative position of the third outlet portlike 48.

Each of the outlet ports like 48 is smaller than the corresponding inletport 36, with the result that the casing I may rotate at a low speedwithout creating enough back pressure in the pump chambers l8 and I9 tocause rotation of shaft When the speed of casing is increased, enoughback pressure is created in the pump chambers I8 and I9 to cause shaft Hto rotate, and on further increase in speed of casing and when the speedof shaft II and rotor I3 has reached a sufficiently high value, sayabove a speed corresponding to 15 or 20 miles an hour in high gear, theoutlet ports like 48 are closed so that there is in effect a directdrive from casing I to shaft through the fluid cushion enclosed in thecompression side of the pump chambers 8 and I9. To this end, one of theoutlet ports like 48 is provided with a centrifugally operated valveshown in Figs. 2, 3, and 4. As shown in Fig. 3, equally spaced valves 52and 53 are provided for the other two outlet ports like 48 in Fig. 2.Valve 5| is slidably mounted in a valve holder 54 which is secured todisc 44 by means of bolts such as 55. Valve 5| is operated on by a cam56 on one end of a lever 5'! which is pivotally mounted on a stud pin 58mounted on disc 44. Lever 51 has a weighted arm 59 which moves outwardlyand causes cam 56 to close valve 5| when disc 44 reaches a high speed asabove described. The movement of weighted arm 59 outwardly may beresisted by a spring 69, one end of which is secured to arm 59, as shownin 6| and the other end to the stud 62 on disc 44, spring 60 tending toreturn arm 59 to its inwardly position against stop 83 as shown ondotted line in Fig. 3. The valves 52 and 53 have centrifugally operatedmechanisms similar to that above described for valve 5|.

The end plate 4 is provided with a plug 64 which serves as a drain plugwhen the casing is in the position in Fig. 2, and as a filling plug whencasing is rotated so that plug 64 is on top.

When the car is climbing a hill, if the speed of the car slows down to apoint where the weighted arms like 59 open the valves like 5|, theclutch automatically begins to slip, allowing the engine to maintain ahigh speed. For this reason it would not be possible to stall theenginewhen this clutch is used.

Assuming the casing is rotating in a counterclockwise direction as seenin Fig. 1, the leading end of the pump chamber IS, in the ring 2, isformed with a radial shoulder or notch 65 which forms a stop againstwhich the vane 29 abuts to prevent reversal of the direction of rotationof easing Similarly the face I] of the pump chamber l8 at its leadingend, terminates in a shoulder or notch 68 to serve as a stop for one ofthe vanes 28, 29 and SE! to prevent reversal of rotation of the casingI.

It will be apparent that the sealing problem for the centrifugallycontrolled valves 5|, 52, and 53 has been substantially eliminatedthrough mounting such mechanism inside of the casing Also, it will beapparent that I have provided a fluid circuit which links with the rotorring 20, the fluid encircling and linking with this ring, the pumpchambers I8 and I9 being arranged at the outermost portion radially ofthis link circuit whereby centrifugal action would keep the pumpchambers 8 and I9 full of oil even though there were some loss due toleakage, the loss appearing centrally of the casing and not peripherallythereof where the pump chambers l8 and I9 are located.

I claim:

1. A hydraulic clutch comprising the combination of a rotatable casinghaving a ring with a plurality of circumferentially spaced eccentricgrooves on the inner side thereof forming the outer walls of pumpchambers, a. rotor ring inside of said casing ring, the periphery ofsaid rotor ring forming the inner wall of said pump chambers, aplurality of vanes on said rotor ring for said chambers, a disc fixed ateach side of said rotor ring, said discs embracing said casing ring andforming the side walls of said pump chambers, inlet ports for saidchambers in one of said discs, outlet ports for said chambers in theother of said discs, and means for controlling the discharge from saidoutlet ports.

2. A hydraulic clutch according to claim 1 wherein said discs haveradial sealing contact with the opposite sides of said casing ring, ashaft for said rotor and means for slidably keying said rotor to saidshaft to facilitate centering said casing ring between said discs.

3. A hydraulic clutch according to claim 1, wherein said controllingmeans comprises centrifugally controlled valve means for controllingsaid outlet ports. 1

4. A hydraulic clutch according to claim 1, wherein said controllingmeans comprises centrifugally controlled valves on said other of saiddiscs for said outlet ports.

5. A hydraulic clutch according to claim 1, comprising notches in saidcasing ring and cooperating with said vanes to prevent reversal of thedirection of rotation of said rotor.

6. A hydraulic clutch comprising the combination of a rotatable casing,a rotor therein, means providing a pump chamber between said casing andsaid rotor, an outlet port in said rotor for said pump chamber, saidoutlet port having such an area as to permit the fluid pumped by saidcasing to pass therethrough freely at idling speed of said casing and athigher speeds restricting the flow of oil and causing said rotor torotate, and centrlfugally controlled Valve means on said rotor in saidcasing for closing said outlet port for positive drive of said rotor bysaid casing.

7. A hydraulic clutch comprising the combination of a casing ring havingrecessed portions forming outer walls of pump chambers, end platessecured to said ring and forming walls of a fluid chamber, a rotorforming the remaining walls of said pump chambers, ports in said rotorpermitting fluid flow from one side of said rotor to the other, inletports in said rotor permitting fluid flow from one side of said rotor tosaid pump chambers, and outlet ports in said rotor permitting fluid fiowfrom said pump chambers to the other side of said rotor.

AUSTIN c; WHITTLESEY.

